5-(But-3-enyl)­pyridinium-2-carboxyl­ate–5-butyl­pyridine-2-carboxyl­ic acid (1/1), a co-crystal from Fusarium moniliforme

In the title co-crystal, C₁₀H₁₁NO₂·C₁₀H₁₃NO₂, the carboxyl­ic acid moiety uses its acid H atom as the donor atom to bind strongly to the negatively charged O atom of the zwitterionic moiety [O...O = 2.557 (2) Å]. Meanwhile, the protonated N atom of the zwitterionic moiety forms a hydrogen bond with the double-bonded O atom of an adjacent zwitterionic moiety [N...O = 2.703 (2) Å] to give rise to a linear chain motif. The butenyl substituent (on the zwitterion) is disordered with respect to a butyl group and the butyl substituent (on the neutral mol­ecule) is disordered with respect to a butenyl group, the site occupancy for both being in an approximate 0.6:0.4 ratio.